Lattice Semiconductor ispClock5400D User Manual

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Lattice Semiconductor ispClock5400D User Manual Manual pdf 28 page image

28ispClock5400D Evaluation BoardLattice Semiconductor User’s GuideHCSLHCSL termination involves a bias network to ground at the driver and no termination at the end of the T-Line.Figure 32 shows the drivers biased through series resistors R16 and R17 (value of 33 ohms) combined with resis-tors R19 and R20 (value of 50 ohms). R19 and R20 also provide T-Line source termination. The receiving end ofthe T-Line does not require any termination. The sense resistors R28 and R29 (value 950 ohms) are not lowenough to serve as termination loads but, provide a way to view the waveforms on the scope. The scope inputimpedance combined with R28 and R29 result in a 20:1 divider of the waveforms at the end of the T-Line.Figure 32. Bank 0 HCSL with On-Board TerminationispClock5406D Standard Evaluation BoardispClockR16R173333R230R240R28R29R300R310BANK_0PJ3J4BANK_0N505pF505pF50 ohms / 64.3 mmmc19/smho05mm3.46/smho05SMA to BNC CableSMA to BNC CableOn Board T-LineOn Board T-LineHCSLBuffers50 ohms / 91 cm950950R1950R2050ScopePower Supply ConnectionsThe evaluation board is powered by a 12V to 5V power supply capable of providing one ampere or more. Theboard can be powered either by a wall adapter with a 2.5mm coaxial power plug at J13 or from a bench supply withbanana plugs at J11 and J12. Once onboard, the supply is regulated (U2) to provide the 3.3V supply needed forVCCD, VCCA, and VCCJ.A second adjustable regulator (U3) provides the VCCO for banks 3 and 5 and it is programmable using the on-board resistors and three of the DIP switches of SW1. To bypass the on-board regulators, zero ohm resistors R106and R116 can be removed from the board to allow external supplies to power the ispClock5406D.TroubleshootingPAC-Designer 5.2: The ispClock5406D PLL Control dialog box of the ispClock5406D I2C Utility(ispClock_5406_I2C_Utility.exe) appears corrupted and the background color obscures the schematicview.To correct the display:1. Exit the ispClock5406D I 2 C Utility.2. From Windows, browse to the \PAC-Designer52\Macro folder of the PAC-Designer installation directory.3. Locate the following files:ispClock_5406_I2C_OutGroup_BI_Sch.emfispClock_5406_I2C_OutGroup_LI_Sch.emfispClock_5406_I2C_OutGroup_UI_Sch.emfispClock_5406_I2C_OutGroup_Sch.emfispClock_5406_I2C_PLL_Sch.emf4. Rename each file so they appear as:ispClock_5400_I2C_OutGroup_BI_Sch.emfispClock_5400_I2C_OutGroup_LI_Sch.emfispClock_5400_I2C_OutGroup_UI_Sch.emf